Sound amplifier



Nov. 27, 1928. I 1,692,841

J. KERsTEN SOUND AMPLIFIER Filed March 22, 1926 2 sh ts shegt l v 2 Lg-L u L 3 Inu mfor 3/ Jacob Kzvsmn A ames;

Nov. 27, 1928. 1,692,841

J.- KERSTEN SOUND AMPLIFIER Filed March 22. 1926 2 ShetS-Sheet 2 Patented Nov. 27, 1928.

UNITED STATES JACOB KERSTEN, OF ALLEGAN, MICHIGAN.

SOUND AMPIJFIER.

Application filed March 22, 1926. Serial No. 96,410.

to construct a device of this character in a simple and economicalmanner and make it of parts which can be very quickly and easily assembled and connected together and which, when assembled, presents a pleasing and attractive appearance. A further object of the invention is to provide a fabric covering for a side of the amplifying device which is very quickly and easily applied and which may be readily detached if it is evernecessary for purposes of repair and replacement and which, when added to the device, greatly increases the attractive appearance thereof. For an understanding of the invention and the constructions embodying the same, by means of which these ends as well as others not at this time stated are attained, reference may be had to the following description taken in connection with the accompanying drawings, in which Fig. 1 is a vertical section through the sound amplifying device.

Fig. 2 is a fragmentary vertical section taken through the lower portion of the device shown in Fig. 1, and in a plane at right angles to the plane of the section shown in Fig. 1.

. igs. 3 and 4: are perspective views of the two members which are used to make the outer enclosing housing of the sound amplifier.

Fig. 5 is a perspective view of one of the binding nuts or plugs, two of which are used in the construction. i a Fig. 6 is an elevation of a detail of the construct-ion used in direct association with and in opposition to, the mouth of the amplifying horn which'is located within the outer housing.

Fi 7 is a perspective view of the a1',u1)lify ing horn.

Fig. 8 is a perspective view of the fabric covering used for one side of the construction.

Fig. 9 is a similar view showing one end thereof drawn together so as to make the covering substantially of conicalshape, and

Fig. 10 is a perspective view of the ring around which the smaller end of the covering shown in Fig. 9, is connected.

Like reference characters refer to like parts in the different figures inthe drawings.

In the construction of the sound amplifying device an outer housing is provided, consisting of two parts. One of these parts is shown in Fig. 3 and is of conical form, as indicated at 1, and has a circular opening 2 made through it at the apex of the cone. At the base of the cone the material from which the cone is made, is materially thickened so as to make a substantially heavy hand 3 from which a narrow annular flange 4 projects, there being an annular recess around the base of the cone inside of the flange 4. At the lower side of the member 1 a notch or recess 5 is cut, the purposes of which will later appear.

The opposite member of the housing is another conical member 6 which, at its base, is but slightly thickened and enlarged, making the rim 7 which is adapted to lit in the annular recess within the flange 4. A circular opening 8 is also made at the apex of the member 6 and a notch or recess 9, similar to the notch or recess 5, is cut in the member 6 so that when the two members 1 and 6 are placed together, the two notches or recesses 5 and 9 are in conjunction and make a single substantially circular opening through the bot-tom of the housing. In the body of the member 6 a large number of openings 10, of any desired shape or form are cut, as shown. WVithin this housing an amplifying horn is placed, the same having a somewhat elongated Vertical neck 11 which passes downwardly through the opening made by the recesses 5 and 9. The upper end of the horn is enlarged and is of the shape indicated at 12 in Figs. 1 and7.

In the assembly of the housing with the horn, a rod 13 is used, thesame being threaded atone end, as indicated at 14, for nearly one half of its length. This rod passes through the born 12 and the horn is held in fixed relation to the rod by means of the nuts 15, one at each side of the horn as best shown in Fig. 1. A nut or plug 16 having an annular flange '17 is threaded onto one end of the rod 13 and fills the opening 2 in the conical member 1', flange 17 extending over the adjacent portions of the member 1 around said opening. A member 18 of paper or like material is mounted'on the rod 14 and located against the inner side of the conicalmemher 1. Said member 18 being of dished form and has a central convex portion or rib 19 through which rod 13 passes, a nut 20 on the rod 18 binding the member 18 against the plug 16/ ,Member 18is positioned directly in front of and in opposition to the open upper end of the horn. A second nut or plug 16 having an annular flange 1'? is threaded onto the opposite end of the rod 13 fitting into the opening 8 in the member 6. It is apparent that by tightening the plugs 16 or 16 on the rod 13 the two conical members 1 and 6 of the housing are firmly held together-and the horn within the housing is rigidly held in proper position with respect to the housing with its lower end extending below the lower side of the housing.

It is designed that'the outer surface of the member 6 shall be covered by a fabric covering thereby disguising the openings and adding to the attractive appearance of the device. To this end a piece of fabric material, preferably of silk, is gathered into cylindrical form, as shown in Fig. 8, and one end is turned back upon itself in a loop 22 around a circular cord 23 and sewed thereover, while the opposite end is gathered together in a much smaller circle and looped back as indicated at 2%, over a split wire ring This covering is applied to the member 6 of the housing, the ring 25 with the loop 24; around it being inserted through the opening 8 in said member 6, while the larger end of the covering is passed around the base of the member 6 and to the inner side thereof.

Accordingly when the parts of the device are assembled as shown in Fig. 1, the fabric covering is clamped in place by the engagement of the base ofthe member 6 in the recess formed in the base of the member 1 and by the plug 16 bearing with its flanges 17* against the portions of the covering inserted through opening 8.

The construction, comprising the Jassembled housing and horn, is adapted to be carried on a suitable supporting base 26 which is formed at its upper side, with a down wardly tapered vertical recess into which the neck 11 of the horn is received. A plate 27 is located within the housing around said neck 11 and long screws 28 pass upwardly through said base 26 and thread through the plate 27, rigidly connecting the housing to the base. In the lower end of the horn 11, a metal member 29 is secured having a threaded projection 30, onto which a loud speaker unit 31 may be screwed, the base 26 being provided with a recess at its under side to receive the unit. The usual wires 32 connected with the loud speaker unit extend therefrom outwardly through a suitable opening in the base, as

shown in Fig 1.

The sound waves given off by the unit 31 are carried through the horn and amplified thereby and delivered against the member 18 which in turn throws the same back, directing said sound waves against the member 6 of the housing so that they pass through the openings 10 therein. The fabric covering interposes little or no obstacle to the passage of the sound waves. as is evident. The construction is relatively simple and inexpensive to make. The members 1 and 6 of the housing may be made of various materials though in practice I prefer to use paperorpapier-mache while th horn may be made of various compositions though in practice I have used paper, plaster of Paris and fabric. Many variations in the matter of the materialsused may be resorted to and many changes in constructive details may also be made without departing from the invention defined in the appended claims. and I consider my invention to be COD'lPlQllBIlSlYG of all forms of strucof said members having sound emitting o en ings therein, means for binding said mem ers together, an amplifying horn located within said shell and extending through a side thereof and adapted to have a loud speaker device attached at its outer end and a fabric covering placed over said member of the shell having openings therethrough, said fabric covering being secured between the two members of the shell at the edges thereof and to the member having said openings therethrough near its apex.

3. A sound amplifying construction, comprising an outer shell formed of two conical members having their edges placed together, each of said members having an opening at its apex, a rod extending through the shell between said openings, plugs screwed onto opposite ends of the rod and fitting into said openings and having parts extending over portions of said members adjacent said openings, an amplifying horn located within the shell and extending at its lower end through the lower side of said shell and adapted to have a loud speaker device fastened to its lower end.

4. A construction containing the elements in combination defined in claim 8, said rod passing through the upper end of the amplifying hornand means on the rod engaging with opposite sides of the horn for fixing the horn in rigid relation to said rod.

5. In a construction of the class described, an outer shell comprising one member of conical shape provided with an annular flange at its edge and an annular recess within said flange, second member also of conian outer shell comprising two dished members having edges together, one of said members at its edge being formed with an annular recess to receive the edge of the other, and each of said members having an opening at its highest point, a fabric covering located around the edges of said member which seats in the recess of the opposite member and covering said member and having its opposite end passed through the opening at the highest point therein, a rod disposed between the members, plugs threaded on opposite ends of the rod and entering into said openings in the member, said plugs having annular lips extending over portions of said members adjacent said openings whereby on tightening the plugs on the rod the members of the housing are tightly secured together and the fabric covering secured in place, an amplifying horn located within the housing and extending at its lower end throughthe bottom thereof and adapted to have a loud speaker unit attached to its lower end, said member of the housing over which the fabric covering is placed, having a plurality of openings therein.

7. In combination, a hollow housing having openings in a side thereof, an amplifying horn located in the housing having an end thereof extending through and beyond a side of said housing, said born at its end within the housing being turned away from the side of the housing having openings therein, said outer end of the horn adapted to have a loud speaker unit attached.

8. In combination, a hollow housing having an opening in the side thereof, a horn located within the housing and having one end thereof extending through and beyond a side of the housing. a supporting base formed with an opening through which the projecting end of the horn extends and also with an enlarged recess in its lower side, means for attaching the housing to the base and means for attaching a loud speaker unit attached to the outer end of the born within said recess in said base, substantially as described.

In testimony whereof I aflix my signature.

JACOB KERSTEN; 

